String NullErrorException

Alright so just a straight forward rundown of my problem is that I'm using

Code (Text):

String map_name = plugin.getConfig().getString("Maps." + storage.current_map + ".name");
 

for getting a name of the current map integer with a String. Now, where it confuses me is the fact it gives me a java.lang.NullPointerException if anyone knows why it's causing this, please do let me know. Thanks.

 

alrighty, thanks.

 

Since you guys have been saying "plugin" could be null. I'm using this

Code (Text):

 
public static me.xfrogx.Main plugin;

public StartGame(me.xfrogx.Main m) {
    plugin = m;
}
 

for getting the main in plugin for the string.

 

Inside of my storage class, where I made the public static ints.

 

Hold up I think I got it. Testing it quick

 

Code (Text):

public class storage implements Listener{
    public static me.xfrogx.Main plugin;

    public storage(me.xfrogx.Main m) {
        plugin = m;
    }

    public static HashMap<Player, UUID> Blue = new HashMap<Player, UUID>();
    public static HashMap<Player, UUID> Red = new HashMap<Player, UUID>();
    public static HashMap<Player, UUID> Spec = new HashMap<Player, UUID>();

    public static String yes = "yes";
    public static String no = "no";

    public static int red_wool = 10;
    public static int blue_wool = 10;

    public static int current_map = 1;
    public static int next_map = 2;
    public static int prev_map = 0;

    public static int countdown = 30;

    public static HashMap<String, Boolean> lobby = new HashMap<String, Boolean>();
    public static HashMap<String, Boolean> starting = new HashMap<String, Boolean>();
    public static HashMap<String, Boolean> in_game = new HashMap<String, Boolean>();
    public static HashMap<String, Boolean> end_game = new HashMap<String, Boolean>();

    public static HashMap<String, Boolean> won = new HashMap<String, Boolean>();


}
 

that's the whole class storage.

 

Code (Text):

at java.lang.Thread.run(Unknown Source) [?:1.8.0_77]
Caused by: java.lang.NullPointerException
        at me.xfrogx.Game.StartGame.startGame(StartGame.java:43) ~[?:?]
        at me.xfrogx.Cmds.StartCMD.onCommand(StartCMD.java:33) ~[?:?]
        at org.bukkit.command.PluginCommand.execute(PluginCommand.java:44) ~[1.9.2.jar:git-Spigot-e6f93f4-d884ab3]
        ... 15 more

 

 

StartCMD is just the void, StartGame. And line 43 is the Strings that're giving me the error.

 

Code (Text):

if (cmd.getName().equalsIgnoreCase("start")) {
    if (p.hasPermission("server.owner")) {

      //  Start.StartGame(p); // called when command is ran \\
        Bukkit.broadcastMessage("TTT");
        StartGame.startGame();

    }
}
 

That's line 33 of the StartCMD.

 

I think I might've found the error, not too sure. But could it possibly be the fact that I'm making a string using an integer?